scholarly journals Influence of Saturation Phenomena on Laser-Excited Atomic Fluorescence Flame Spectrometry

1973 ◽  
Vol 28 (2) ◽  
pp. 273-279
Author(s):  
J. Kühl ◽  
S. Neumann ◽  
M. Kriese
Keyword(s):  
Power Density ◽  
Laser Power ◽  
Atomic Emission ◽  
Equation Model ◽  
Laser Power Density ◽  
Atomic Level ◽  
Dye Laser ◽  
Atomic Fluorescence ◽  
Emission Flame ◽  
Flame Spectrometry

Using a simple rate equation model, the laser power density Ic necessary to reach 50% of the saturation limited population of the excited atomic level under typical flame conditions is calculated. For Na atoms aspirated into the flame a saturating power density for irradiation with a narrow dye laser line (bandwidth 0.033 Å) of Ic ~ 0.4 kW/cm2 was determined. With the aid of a dye laser with an appropriate laser power density, analytical curves for Na were measured yielding a detection limit of 0.2 ng/ml. This sensitivity is comparable with the best results obtained by atomic emission flame spectrometry.

Comparison of Nebulization-Spray Chamber Arrangements for Atomic Fluorescence and Atomic Emission Flame Spectrometry

1981 ◽  
Vol 35 (2) ◽  
pp. 149-152 ◽  
Author(s):  
J. J. Horvath ◽  
J. D. Bradshaw ◽  
J. D. Winefordner
Keyword(s):  
Detection Limits ◽  
Atomic Emission ◽  
Ultrasonic Nebulizer ◽  
Atomic Fluorescence ◽  
Batch Type ◽  
Uptake Rates ◽  
Pneumatic Nebulizer ◽  
Emission Flame ◽  
Flame Spectrometry ◽  
Solution Uptake

Ten different commercial atomic absorption nebulizer-chamber systems with a capillary burner and three laboratory-constructed ultrasonic nebulizer chamber systems with a miniflame burner are compared with respect to solution uptake rates, concentrational and absolute detection limits, efficiencies of nebulization, and common flame spectrometric interferences. Measurements of both flame atomic emission (Sr, Ca, K, Na) and flame atomic fluorescence (Mg, Cu, Pb) were performed for all cases. The ultrasonic and pneumatic nebulizer systems resulted in about the same concentrational detection limits, but the former resulted in ∼102X lower absolute detection limits. The batch type ultrasonic nebulizer gave much higher nebulization efficiencies than the continuous flow ultrasonic nebulizer or any of the pneumatic nebulizer systems. Chemical interferences were approximately the same in all nebulizer-burner systems. Nebulizer chambers with a J-bead resulted in lower detection limits than the same systems without J-beads.

Some causes of bending of analytical curves in atomic emission flame spectrometry

1966 ◽  
Vol 36 ◽  
pp. 42-56 ◽  
Author(s):  
T.J. Vickers ◽  
L.D. Remington ◽  
J.D. Winefordner
Keyword(s):  
Atomic Emission ◽  
Emission Flame ◽  
Flame Spectrometry

Experimental Study on Testing Ni-Containing Stainless Steel Protective Coatings by Pulsed Laser Scratching

2010 ◽  
Vol 43 ◽  
pp. 651-656
Author(s):  
Ai Xin Feng ◽  
Yu Peng Cao ◽  
Chuan Chao Xu ◽  
Huai Yang Sun ◽  
Gui Fen Ni ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Power Density ◽  
Laser Power ◽  
Protective Coatings ◽  
Three Dimensional ◽  
Pulsed Laser ◽  
Laser Power Density ◽  
The Matrix ◽  
The Impact

In the experiment, we use pulsed laser to conduct discrete scratching on Ni-containing stainless steel protective coatings to test residual stress situation after the matrix is scratched; then to analyze the the impact of the impact stress wave on coating - substrate bonding strength according to the test results, finally to infer the laser power density range within which it occurs coating failure. The study shows that: after laser discrete scratching, the residual stress of the center of the laser-loaded point on matrix surface gradually reduces when the pulsed laser power density increases. The matrix produces a corresponding residual compressive stress under the laser power density reaches a certain value. The actual failure threshold values are 12.006 GW/cm2, 11.829GW/cm2 and 12.193GW/cm2 measured by the three-dimensional topography instrument testing the discrete scratch point of three groups of samples and verified by using a microscope

Numerical Simulation and Applications of a Method for Attenuating Laser Power Density

2013 ◽  
Vol 50 (2) ◽  
pp. 022201
Author(s):  
王振宝 Wang Zhenbao ◽  
冯国斌 Feng Guobin ◽  
杨鹏翎 Yang Pengling ◽  
冯刚 Feng Gang ◽  
闫燕 Yan Yan
Keyword(s):  
Numerical Simulation ◽  
Power Density ◽  
Laser Power ◽  
Laser Power Density

Measurement of microsamples in atomic emission and atomic fluorescence flame spectrometry

1972 ◽  
Vol 60 (1) ◽  
pp. 55-64 ◽  
Author(s):  
J. R. Sarbeck ◽  
P. A. St. John ◽  
J. D. Winefordner
Keyword(s):  
Atomic Emission ◽  
Atomic Fluorescence ◽  
Flame Spectrometry

scholarly journals Investigation on Residual Stress Loss during Laser Peen Texturing of 316L Stainless Steel

2019 ◽  
Vol 9 (17) ◽  
pp. 3511 ◽  
Author(s):  
Kangmei Li ◽  
Yifei Wang ◽  
Yu Cai ◽  
Jun Hu
Keyword(s):  
Residual Stress ◽  
Compressive Stress ◽  
Power Density ◽  
Laser Power ◽  
Surface Deformation ◽  
Laser Power Density ◽  
Residual Compressive Stress ◽  
Laser Spot ◽  
Residual Tensile Stress ◽  
Spot Radius

Laser peen texturing (LPT) is a novelty way of surface texturing based on laser shock processing. One of the most important benefits of LPT is that it can not only fabricate surface textures but also induce residual compressive stress for the target material. However, the residual stress loss leads to partial loss of residual compressive stress and even causes residual tensile stress at the laser spot center. This phenomenon is not conducive to improving the mechanical properties of materials. In this study, a numerical simulation model of LPT was developed and validated by comparison of surface deformation with experiments. In order to investigate the phenomenon of residual stress loss quantitatively, an evaluation method of residual stress field was proposed. The effects of laser power density and laser spot radius on the residual stress, especially the residual stress loss, were systematically investigated. It is found that with the increase of laser power density or laser spot radius, the thickness of residual compressive layer in depth direction becomes larger. However, both the magnitude and the affecting zone size of residual stress loss will be increased, which implies a more severe residual stress loss phenomenon.

Simultaneous multi-element atomic emission flame spectrometry with an image vidicon detector

1974 ◽  
Vol 69 (2) ◽  
pp. 455-460 ◽  
Author(s):  
D.O. Knapp ◽  
N. Omenetto ◽  
L.P. Hart ◽  
F.W. Plankey ◽  
J.D. Winefordner
Keyword(s):  
Atomic Emission ◽  
Emission Flame ◽  
Flame Spectrometry

Tuning the Defects in AgO Nanoparticles/Graphene Bilayers System by Laser Power Density

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
H. Ferreira ◽  
M. Briones2, M. Camilo ◽  
G. Poma ◽  
Maria Quintana ◽  
A. Champi
Keyword(s):  
Power Density ◽  
Laser Power ◽  
Laser Power Density

Characterizing the Effect of Laser Power Density on Microstructure, Microhardness, and Surface Finish of Laser Deposited Titanium Alloy

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Rasheedat M. Mahamood ◽  
Esther T. Akinlabi ◽  
Mukul Shukla ◽  
Sisa Pityana
Keyword(s):  
Surface Roughness ◽  
Titanium Alloy ◽  
Power Density ◽  
Surface Finish ◽  
Laser Power ◽  
Optical Microscope ◽  
Laser Power Density ◽  
Grain Structure ◽  
Selection Of

This paper reports the effect of laser power density on the evolving properties of laser metal deposited titanium alloy. A total of sixteen experiments were performed, and the microstructure, microhardness and surface roughness of the samples were studied using the optical microscope (OP), microhardness indenter and stylus surface analyzer, respectively. The microstructure changed from finer martensitic alpha grain to coarser Widmastätten alpha grain structure as the laser power density was increased. The results show that the higher the laser power density employed, the smoother the obtained surface. The microhardness initially increased as the laser power density was increased and then decreased as the power density was further increased. The result obtained in this study is important for the selection of proper laser power density for the desired microstructure, microhardness and surface finish of part made from Ti6Al4V.

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